Friction clutch



- Dec. 12, .1939."

w. s'. WOLFRAM FRICTION CLUTCH Filed Feb. 27; 19:59

3nn'entor Patented Dec. 12, 1939 t v v UNITED STATESPATENT OFFICE I FRICTION CLUTCH William S. Wolfram, Dayton, Ohio, assignor to General Motors Corporation, Detroit, Mich, a corporation of Delaware Application February 27, 1939, Serial No. 258,646

4 Claims. (Cl. 192-68) This invention relates to friction clutches and clutch plate l9, provided with facings 20. This has been made as the result of an effort to improve driven plate has a torque cushioning spring conthefriction clutch through the instrumentality' nection 2| with a hub 23 mounted to rotate with of which'the engine of a motor vehicle drives the shaft H. A pressure plate 25 is adapted to be input shaft of the transmission. 'moved toward the flywheel and grip the driven 5 In clutches of the kind referred to, there is plate l9. usually provided a cover fixedly secured to but A plurality of angular spring clips 21 distributed having an abutment portion spaced from the fiyin a circular series are attached to the cover at wheel on the engine shaft. Adapted to be gripped 29. These clips have their opposite ends disposed between the face of the flywheel and an axially at a greater radial distance than the attachments l0 movable pressure plate is the driven plate. A at 29 and at these greater distances are attached suitable spring in abutment with the cover plate at 3| to the pressure plate. The pressure plate biases the pressure plate to its active position. is thus centralized relative to the cover I3 and Means is provided to release the pressure plate the flywheel 9. The intermediate wall 33 of the from the action of e Spring d so yielding clip extends radially as shown. When the clip 15 means i provided o r ciprocate the pressure is unloaded this wall 33 extends at an angle to p e wa from e flyw .When e u c is the end portions 35 and 31 as shown by full lines to be released. The present invention relates to in Figure 3. The length of each spring clip 21 this kind of clutch and it includes an improve i th refore slightly less when unloaded than 0 ment in t m unti 0f t e C utc en when the intermediate wall is at right angles to Spri g and the parts associated therewith. the end portions. Whenthe clips are in the posialso includes improvements in the mechanism by tion shown by full lines in Figure 3, the pressure which the p r plate i cen r lly l ated r laplate is in clutch releasing position. When in the tive to and is made to rotate with the flywheel d tted line position the clutch is engaged. 25 d y Which e P essu Plate iS moved y To move the pressure plate to clutch engaging 25 from the flywheel W t e Clu S d sen edposition there is used a coned or Belleville spring The main Object of the invention i briefly marked 39. Its outer end is secured to the interto improve d S plify the clutch in the mediate walls of the clips 21 by rivets 4|, reinforcabove particulars by the use of structure which ing members being shown at 43. A clutch throw- Shall be highly efiicieht, comparatively penout collar is shown at 45. It is adapted to engage SiVe and e y t asse l 'a plurality of segments 41, which segments have As a further object the invention employs a radial arms 48 riveted to the Belleville spring at known form of Belleville spring-and provides a 5| and interengaging parts at 53. The arms errmounting therefor which eliminates the friction tend between the slots 55 provided, as usual in between such a spring and its fulcrum contact this type of spring. 35 region, which friction has been present in certain The Belleville spring is normally coned with Its. prior constructions. Other objects and advanapex adjacent the collar 45. It is prestressed tages will be understood fromthe following deassembly so that it straightens out the intermedip Oh the g! ate walls 33 of the clips 21 and forces the pressure 40 Figure 1 is a transverse sectional view on line plate to active position. As in prior usage the 4o 1-! of Fi ur 2. annular band of the spring adiacent its periphery Figure 2 is a view in elevation partly broken is unbroken by slots This band therefore has a yleverage between the region at 35 and the region Figure 3 is a sectional view of a portion of the at 31 of the spring clips to apply the clutch. In assembly shown in Figure 1 with parts displaced so doing, the pressure of the spring operates 45 from the position they occupy in Figure 1. through parts 31 of the spring clips and takes an Figure 4 is a view as seen from line 4-4 of abutment at the point where arms 35 of the clips Figure 2. are secured to the cover. When pressure is ap- Referrine by re e e e ct rs o th drawplied at the throwout sleeve the load is taken mg, numeral 1 is applied to the engine shaft. A from the cover and the latent spring energy in the 50 flywheel 9 is secured to the engine shaft by fastenclip restores the intermediate wall to the angular ing means II. A cover l3 shaped as shown is position shown by Figure 3 and the clutch is secured to the flywheel by a plurality of fastening released. l I means It. A driven shaft ll coaxial with shaft By the arrangement described the cover secured a l enters the cover enclosure and carries a driven to the flywheel centers the pressure plate and spring, thus avoiding the more conventional driving lugs. In prior usage a certain amount of friction between the Belleville spring and its fulcrum was unavoidable. In the present case this friction no longer occurs. The construction is very simple and the parts are obviously inexpensive.

I claim:

1. In a clutch having a flywheel, a cover, a reciprocable pressure plate and a driven member adapted to be gripped between the flywheel and pressure plate, yielding clips having axially and radially spaced ends secured to said cover and the pressure plate and radially extending intermediate parts, plate spring means adapted to ef: fect clutch engagement, means to attach the outer margin of said spring means to said intermediate parts of said clips and throwout means operable upon the inner margin of said spring means.

2. The invention defined by claim 1, said spring means being in the form of a Belleville washer.

3. The invention defined by claim 1, each of said spring clips having its intermediate wall extending at an acute angle to its end walls when unloaded and adapted to be brought into right angular relation with said end walls by the clutch engaging action of the spring means.

4. The invention defined by claim 1, said throwout means including a reciprocable member and separable abutments engaged thereby, said abutment members being secured to the radially inner portions of said spring means.

WILLIAM S. WOLFRAM. 

